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diff --git a/DOCS/OUTDATED-tech/libvo.txt b/DOCS/OUTDATED-tech/libvo.txt deleted file mode 100644 index 245d29eade..0000000000 --- a/DOCS/OUTDATED-tech/libvo.txt +++ /dev/null @@ -1,173 +0,0 @@ -libvo --- the library to handle video output by A'rpi, 2002.04 -============================================ - -Note: before start on this, read colorspaces.txt ! - -The constants for different pixelformats are defined in img_format.h, -their usage is mandatory. - -WARNING: Please keep in mind that some of this information may be out-dated, -so if you are working on a new vo, consider submitting preliminary patches -very early on. Currently vo_gl is one of the more up-to-date VOs to use -as reference if you are unsure about something and do not want to ask on the -list. -vo_vdpau and vo_direct3d may be a good choice, too, they use different -approaches closer to the sometimes convoluted way DirectX works. - -Each vo driver _has_ to implement these: - - preinit(): - init the video system (to support querying for supported formats) - - uninit(): - Uninit the whole system, this is on the same "level" as preinit. - - control(): - Current controls (VOCTRL_QUERY_FORMAT must be implemented, - VOCTRL_DRAW_IMAGE, VOCTRL_FULLSCREEN, VOCTRL_UPDATE_SCREENINFO - should be implemented): - VOCTRL_QUERY_FORMAT - queries if a given pixelformat is supported. - It also returns various flags decsirbing the capabilities - of the driver with teh given mode. for the flags, see - file vfcaps.h ! - the most important flags, every driver must properly report - these: - 0x1 - supported (with or without conversion) - 0x2 - supported without conversion (define 0x1 too!) - 0x100 - driver/hardware handles timing (blocking) - also SET sw/hw scaling and osd support flags, and flip, - and accept_stride if you implement VOCTRL_DRAW_IMAGE (see bellow) - NOTE: VOCTRL_QUERY_FORMAT may be called _before_ first config() - but is always called between preinit() and uninit() - VOCTRL_GET_IMAGE - libmpcodecs Direct Rendering interface - You need to update mpi (mp_image.h) structure, for example, - look at vo_x11, vo_sdl, vo_xv or mga_common. - VOCTRL_DRAW_IMAGE - replacement for the current draw_slice/draw_frame way of - passing video frames. by implementing SET_IMAGE, you'll get - image in mp_image struct instead of by calling draw_*. - unless you return VO_TRUE for VOCTRL_DRAW_IMAGE call, the - old-style draw_* functils will be called! - Note: draw_slice is still mandatory, for per-slice rendering! - VOCTRL_RESET - reset the video device - This is sent on seeking and similar and is useful if you are - using a device which prebuffers frames that need to flush them - before refilling audio/video buffers. - VOCTRL_PAUSE - VOCTRL_RESUME - VOCTRL_GUISUPPORT - return true only if driver supports co-operation with - MPlayer's GUI (not yet used by GUI) - VOCTRL_SET_EQUALIZER - set the video equalizer to the given values - two arguments are provided: item and value - item is a string, the possible values are (currently): - brightness, contrast, saturation, hue - VOCTRL_GET_EQUALIZER - get the current video equalizer values - two arguments are provided: item and value - item is a string, the possible values are (currently): - brightness, contrast, saturation, hue - VOCTRL_ONTOP - Makes the player window stay-on-top. Only supported (currently) - by drivers which use X11, except SDL, as well as directx and - gl2 under Windows. - VOCTRL_BORDER - Makes the player window borderless. - VOCTRL_FULLSCREEN - Switch from and to fullscreen mode - VOCTRL_GET_PANSCAN - VOCTRL_SET_PANSCAN - Needed to implement pan-scan support ('w' and 'e' keys during - playback in fullscreen mode) - VOCTRL_START_SLICE - Called before the first draw_slice of each frame, useful if - you need to do some set-up work. - VOCTRL_DRAW_EOSD - Required for EOSD (ASS subtitle) support. Provides all - information necessary to draw the EOSD for the current video - frame. - VOCTRL_GET_EOSD_RES - Required for EOSD (ASS subtitle) support. Informs the ASS - renderer about the properties of the drawing area (size, - borders). - VOCTRL_SET_DEINTERLACE - VOCTRL_GET_DEINTERLACE - Get or set deinterlacing status for VOs that support some kind - of deinterlacing. - VOCTRL_UPDATE_SCREENINFO - Should set the xinerama_x, xinerama_y, vo_screenwidth and - vo_screenheight appropriately for the currently used - monitor and -xineramascreen option. - Usually should simply call the w32_update_xinerama_info or - update_xinerama_info function. - By supporting this, the VO also requests the newer API - that sets vo_dx, vo_dy etc. appropriately before config() - is called. - - config(): - Set up the video system. You get the dimensions and flags. - width, height: size of the source image - d_width, d_height: wanted scaled/display size (it's a hint) - Flags: - 0x01 - force fullscreen (-fs) - 0x02 - allow mode switching (-vm) - 0x04 - allow software scaling (-zoom) - 0x08 - flipping (-flip) - They're defined as VOFLAG_* (see libvo/video_out.h) - - IMPORTANT NOTE: config() may be called 0 (zero), 1 or more (2,3...) - times between preinit() and uninit() calls. You MUST handle it, and - you shouldn't crash at second config() call or at uninit() without - any config() call! To make your life easier, vo_config_count is - set to the number of previous config() call, counted from preinit(). - It's set by the caller (vf_vo.c), you don't have to increase it! - So, you can check for vo_config_count>0 in uninit() when freeing - resources allocated in config() to avoid crash! - - You should implement VOCTRL_UPDATE_SCREENINFO so that vo_dx, vo_dy, - vo_dwidth and vo_dheight are already pre-set to values that take - aspect and -geometry into account. It is also necessary to properly - support multi-monitor setups (if based on x11_common, w32_common). - - draw_slice(): this displays YV12 pictures (3 planes, one full sized that - contains brightness (Y), and 2 quarter-sized which the colour-info - (U,V). MPEG codecs (libmpeg2, opendivx) use this. This doesn't have - to display the whole frame, only update small parts of it. - If this is not supported, it must be signaled in QUERY_FORMAT with - VOCAP_NOSLICES. - - draw_frame(): this is the older interface, this displays only complete - frames, and can do only packed format (YUY2, RGB/BGR). - Win32 codecs use this (DivX, Indeo, etc). - If you implement VOCTRL_DRAW_IMAGE, you do not need to implement draw_frame. - - draw_osd(): this displays subtitles and OSD. - It's a bit tricky to use it, since it's a callback-style stuff. - It should call vo_draw_text() with screen dimension and your - draw_alpha implementation for the pixelformat (function pointer). - The vo_draw_text() checks the characters to draw, and calls - draw_alpha() for each. As a help, osd.c contains draw_alpha for - each pixelformats, use this if possible! - Note that if you do not draw directly onto the video you should - use vo_draw_text_ext() which allows you to specify the border - values etc. needed to draw DVD menu highlights at the correct place. - If you do not want to implement this, you can still use -vf - expand=osd=1 to draw the OSD, or even implement code to insert - this filter automatically. - Make sure you set VFCAP_OSD depending on whether you implemented it - or not. - - NOTE: This one will be obsolete soon! But it's still useful when - you want to do tricks, like rendering osd _after_ hardware scaling - (tdfxfb) or render subtitles under of the image (vo_mpegpes, sdl) - - NOTE2: above NOTE is probably wrong, there are currently no plans to - obsolete draw_osd, though there is the more advanced EOSD support for - ASS subtitles. - - flip_page(): this is called after each frame, this displays the buffer for - real. This is 'swapbuffers' when doublebuffering. - Try to do as little work here as possible, since that affect jitter/ - A-V sync. |